Weight-adjustable dumbbell

ABSTRACT

A weight-adjustable dumbbell includes a dumbbell base, which has a plurality of locating holes, a plurality of weights, which are detachably mountable on the dumbbell base, each having a plurality of through holes corresponding to the locating holes of the dumbbell bases, and a plurality of lock pins insertable into the locating holes of the dumbbell base and the through holes of the weights to selectively secure the weights to the dumbbell base.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a dumbbell and more particularly, to a weight-adjustable dumbbell.

2. Description of the Related Art

When making a body building exercise, a dumbbell is commonly used to train the muscles. There are dumbbells that allow the user to adjust the total weight. A weight-adjustable dumbbell generally comprises a bar, a plurality of weights selectively detachably mounted on the ends of the bar, and two screw caps respectively threaded onto the ends of the bar to lock the loaded weights. When adjusting the total weight of the dumbbell, the user must detach the screw caps from the bar, and then remove some of the weights from the bar or attach new weights to the bar, and then fasten the screw caps to the bar again after loading of the selected weights. This adjusting procedure is complicated. Further, if the end caps are not fastened tight or the weights are not evenly arranged on the two ends of the bar, the user may be unable to keep the dumbbell in balance when lifting the dumbbell, thereby causing an accident.

SUMMARY OF THE INVENTION

The present invention has been accomplished under the circumstances in view. It is one object of the present invention to provide a dumbbell, which allows the user to adjust the total weight of the dumbbell conveniently.

To achieve the above-mentioned object, the weight-adjustable dumbbell provided by the present invention comprises a dumbbell base having at least one locating hole; a plurality of weights detachably mountable on the dumbbell base, the weights each having at least one through hole corresponding to the at least one locating hole of the dumbbell base; and at least one lock pin insertable into the at least one locating hole of the dumbbell base and insertable into the at least one through hole of the weights to selectively secure the weights to the dumbbell base.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a weight-adjustable weight according to the present invention.

FIG. 2 is an exploded view of the weight-adjustable dumbbell according to the present invention.

FIG. 3 is a front view of the weight-adjustable dumbbell according to the present invention.

FIG. 4 is a side view of the weight-adjustable dumbbell according to the present invention.

FIG. 5 is a top view of the weight-adjustable dumbbell according to the present invention.

FIG. 6 is a sectional view taken along line 6-6 of FIG. 4.

FIG. 7 is a sectional view taken along line 7-7 of FIG. 3.

FIG. 8 is a sectional view taken along line 8-8 of FIG. 3.

FIG. 9 is a schematic drawing of the present invention, showing a number of weights separated from the dumbbell base.

DETAILED DESCRIPTION OF THE INVENTION

Referring to FIG. 1, a weight-adjustable dumbbell in accordance with the present invention is shown comprising a dumbbell base 11, a plurality of weights 21-29, and two lock pins 91. The weights 21-29 are respectively arranged at two sides of the dumbbell base 11. The two lock pins 91 are detachably fastened to the dumbbell base 11 at two sides.

Referring to FIGS. 2 through 5, the dumbbell base 11 comprises a bar 12, and a holder portion 13 at each of the two distal ends thereof. Each holder portion 13 has a recess 14 at each of the front and back sides, a groove 15 at the bottom side, a plurality of locating holes 16 symmetrically arranged at two sides at different elevations in a staggered manner between the two recesses 14, numerical marks 19 marked in the front recess 14 corresponding to the locating holes 16 for indicating the total weight of the weight-adjustable dumbbell, a substantially inverted U-shaped stop plate 17 mounted in the back recess 14 around the corresponding locating holes 16, and an open chamber 18 at an outer side in communication between the locating holes 16. Further, the total weight of the dumbbell base 11 is about 5 lbs.

The weights 21-29 are heavy plates each having a weight about 2.5 lbs. The weights 21-29 each have a slot 31-38, and a substantially inverted U-shaped mounting flange 4148 adjacent to the slot 31-38. The substantially inverted U-shaped mounting flange 4148 has two sidewalls 51-58 and a top wall 61-68 connected between the sidewalls 51-58. The weights 21-29 have a different pitch between the sidewalls 51-58 and a different elevation among the top walls 61-68. Further, a connecting rod 39 is connected between the two outer weights 29.

Referring to FIGS. 4 and 5, when the weights 21-29 are set in the dumbbell base 11 at two sides, the mounting flanges 41 of the weights 21 are respectively received in the open chambers 18 of the two holder portions 13 of the dumbbell base 11; the mounting flanges 42 of the weights 22 are respectively inserted through the slots 31 of the weights 21 into the space between the two sidewalls 51; the mounting flanges 43 of the weights 23 are respectively inserted through the slots 32 of the weights 22 into the space between the sidewalls 52; the mounting flanges 44-48 of each of the other weights 24-28 are respectively inserted through the slots 33-37 of each of the weights 23-27 in the space between the corresponding sidewalls 53-57. When assembled, the mounting flanges 41-48 are attached to one another in proper order to keep the top walls 61-68 vertically spaced from one another at a predetermined distance, and the top side of the connecting rod 39 is spaced from the top wall 68 of the weight 28 at a distance.

The top wall 61-68 of the mounting flange 41-48 has a downwardly extending pointed locating pin 81. The locating pin 81 has a head 82 protruding over the top side of the top wall 61-68. The head 82 has a top recess 83. When the weights 21-29 are set in the dumbbell base 11 at two sides, the heads 82 of the locating pins 81 at the top walls 61 are respectively received in respective open chamber 18 in the holder portions 13; the bottom ends of the locating pins 81 at the top walls 61 are respectively received in the recesses 83 of the locating pins 81 at the top walls 62; the bottom ends of the locating pins 81 at the top walls 62 are respectively received in the recesses 83 of the locating pins 81 at the top walls 63; the bottom ends of the locating pins 81 at the top walls 63-67 are respectively received in the recesses 83 of the locating pins 81 at the top walls 64-68; the; the bottom ends of the locating pins 81 at the top walls 68 are respectively received in respective holes 84 at the connecting rod 39. Therefore, the weights 21-29 are secured together by means of the locating pins 81.

As shown in FIGS. 2 and 6, the sidewalls 51-58 of the mounting flanges 4148 each have at least one through hole 71-78 corresponding to each other, and the connecting rod 39 between the two weights 29 has two through holes 79. When the weights 21-29 are set in the dumbbell base 11 at two sides, the through holes 71-78 of the mounting flanges 4148 and the through holes 79 of the connecting rod 39 are in communication with the respective locating holes 16 at the dumbbell base 11, and the topmost through holes 71-78 of the mounting flanges 41-48 are respectively communicated with one of the locating holes 16 at the holder portion 13.

As shown in FIGS. 5-8, each lock pin 91 has a round shank 93, a head 94 at one end of the round shank 93, and a retaining device 95 at the other end of the round shank 93. The retaining device 95 is comprised of two steel balls 96 and a spring member 97. The steel balls 96 are movably mounted in the round shank 93 and partially forced out of the periphery of the round shank 93 by the spring member 97.

The round shank 93 of each of the lock pins 91 can be respectively inserted through the locating holes 16 of the dumbbell base 11 and the through holes 71-79 of the weights 21-29, keeping the head 94 of each of the lock pins 91 respectively received in the recess 14 at the front side of the holder portion 13 at each of the two distal ends of the dumbbell base 11 and the retaining device 95 of each of the lock pins 91 respectively suspending in the recess 14 at the back side of the holder portion 13 at each of the two distal ends of the dumbbell base 11. Therefore, the steel balls 96 of each lock pin 91 are forced outwards by the respective spring member 97 into engagement with the inside wall of the respective recess 14 to lock the weights 21-29 to the dumbbell base 11.

Referring to FIGS. 3-8 again, if the locating pins 91 are set in the locating holes 16 corresponding to “50” of the numerical marks 19, the round shanks 93 of the locating pins 91 are respectively inserted through the through holes 71-79 corresponding to the corresponding locating holes 16 and positioned in the respective holder portions 13, joining the weights 21-29 to the dumbbell base 11. When the user holds the bar 12 of the dumbbell base 11 to lift the weight-adjustable dumbbell, the weights 21-29 are carried by the dumbbell base 11 by means of the lock pins 91 and the locating pins 81, therefore the user can proceed with an about 50 lbs weight training.

Referring to FIG. 9, if the user wishes to proceed with an about 30 lbs weight training, the user must insert the lock pins 91 in the through holes 16 corresponding “30” of the numerical marks 19. At this time, the round shanks 93 of the lock pins 91 are respectively inserted through the through holes 71-75 to secure the weights 21-25 to the dumbbell base 11. When the user lifts the dumbbell base 11, the weights 21-25 are moved with the dumbbell base 1, making a 30 lbs weight training. Because the weights 26-28 are supported on the connecting rod 39 between the weights 29 and attached to one another, the weights 26-29 are prohibited from biasing, and the user can conveniently load and unload the weights 21-29. Further, when the lock pins 91 are mounted in the through holes 16 corresponding to “5” of the numerical marks 19, the lock pins 91 are positioned in the holder portions 13 of the dumbbell base 11, and the user can use the weight of 5 lbs of the dumbbell base 11 itself to make a weight training.

Although a particular embodiment of the invention has been described in detail for purposes of illustration, various modifications and enhancements may be made without departing from the spirit and scope of the invention. Accordingly, the invention is not to be limited except as by the appended claims. 

1. A dumbbell comprising: a dumbbell base having at least one locating hole; a plurality of weights detachably mountable on said dumbbell base, said weights each having at least one through hole corresponding to the at least one locating hole of said dumbbell base; and at least one lock pin insertable into the at least one locating hole of said dumbbell base and the at least one through hole of said weights to selectively secure said weights to said dumbbell base.
 2. The dumbbell as claimed in claim 1, wherein said weights each have a slot and a mounting flange adjacent to the slot, said mounting flange having two sidewalls and a top wall connected between said sidewalls, said sidewalls being provided with the at least one through hole of the respective weight, the mounting flange of one of said weights being overlapped on the mounting flange of another one of said weights to have each through hole of each weight in alignment with one locating hole of said dumbbell base when a number of said weights are attached to said dumbbell base.
 3. The dumbbell as claimed in claim 2, wherein said dumbbell base comprises at least one open chamber in communication with said locating holes for receiving the mounting flanges of said weights.
 4. The dumbbell as claimed in claim 1, wherein said weights each comprise a locating pin, said locating pin having a recess at one end thereof; wherein the locating pin of one of said weights is positioned in the recess of the locating pin of another one of said weights when a number of said weights are mounted on said dumbbell base.
 5. The dumbbell as claimed in claim 1, wherein said dumbbell base comprises a bar and two holder portions respectively provided at two distal ends of said bar; the at least one locating hole of said dumbbell is respectively defined in said holder portions.
 6. The dumbbell as claimed in claim 1, further comprising a connecting rod fixedly connected between two of said weights for supporting the others of said weights in said dumbbell base; said dumbbell base comprises at least one groove for accommodating said connecting rod.
 7. The dumbbell as claimed in claim 1, wherein said at least one lock pin each comprises a shank, and a retaining device provided at one end of said shank for securing the respective lock pin to said dumbbell base.
 8. The dumbbell as claimed in claim 7, wherein said retaining device comprises at least one steel ball movably mounted in the shank of the respective lock pin and a spring member mounted in the shank of the respective lock pin to support said at least one steel ball and to force said at least one steel ball partially out of the periphery of the shank of the respective lock pin. 